Two opposite sides of a parallelogram each have a length of #4 #. If one corner of the parallelogram has an angle of #(5 pi)/8 # and the parallelogram's area is #12 #, how long are the other two sides?

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Answer 1 · 2016-05-26T12:10:02

The other two sides are #2.77# units lomg.

Area of a parallelogram is given by #axxbxxsintheta#, where #a# and #b# are two sides of parallelogram and #theta# is angle included between them.

As here one pair of sides are #4# units, included angle is #(5pi)/8# and area is #12#, we have

#4xxbxxsin((5pi)/8)=12# or #4xxbxx0.9239=12#

Hence #b=(12xx0.9239)/4=2.7717#

or #b=2.77#